Bhagavad Gita · Chapter 13: The Field and the Knower of the Field
Bhagavad Gita 13.22
उपद्रष्टानुमन्ता च भर्ता भोक्ता महेश्वरः ।
परमात्मेति चाप्युक्तो देहेऽस्मिन्पुरुषः परः ॥
upadraṣṭānumantā ca bhartā bhoktā maheśvaraḥ | paramātmeti cāpyukto dehe'sminpuruṣaḥ paraḥ ||
The supreme spirit in this body is also called the witness, the one who gives consent, the sustainer, the experiencer, the great Lord, and the supreme self.
Modern context
The supreme spirit in the body is given many names: witness, consenter, sustainer, experiencer, great Lord, supreme self. 'Witness' and 'consenter' are especially interesting. The deepest self watches everything and permits it, without interfering. It is like a patient host who lets guests come and go. Knowing this presence is within can bring great steadiness.